A new family of molecules that stop cancer cells covering themselves with sugar could prevent the spread of tumours, scientists have learned.

The same drugs might be able to control infectious bugs, which also need a sugar coating.

Many biological cells, including cancer cells and bacteria, use sugar particles to communicate with their environment and each other.

When cancer spreads through the body or microbes invade a human host they make contact with other cells via their sugary overcoats.

To form the complex chains and branched structures that decorate their surfaces, the cells have to join separate sugar building blocks together. For this they rely on enzymes called glycosyltransferases.

The new molecules, known as synthetic UDP-galactose derivatives, are shaped in such a way that they block these enzymes and stop the sugar structures forming.

Scientists believe they have the potential to disrupt harmful processes such as cancer metastasis — or spread — and bacterial infection.

Lead researcher Dr Gerd Wagner, from the University of East Anglia, said: “This exciting discovery of a potent enzyme inhibitor with a completely new mechanism of action has considerable therapeutic potential in cancer, inflammation and infection.

“Our results also provide a general strategy for how to design and improve such inhibitors in the future.”

The findings are reported in the latest Nature Chemical Biology journal. The scientists made their discovery by studying the detailed molecular structure of the enzymes and the UDP-galactose derivatives.